Quote Originally Posted by HenrikOlsson View Post
...But simply setting a flag that there's been an interrupt and then poll that flag in the main loop is...well of not much use and a waste resources. Just poll the interrupt flag (and remember to reset it) instead....
It's not a rant if you guys help me. I didn't know that about the IOC flag being set regardless (I've done a lot of reading on Interrupt - remembering what I read is something else entirely).

Richard did find the real problem. I was using 0.01uF for the encoder and the switch. This is what it looked like at higher resolution:




Then I changed for 0.1uF:



Just a blip on this one:




But I have to use 0.01uF on the encoder or else they don't act properly.


So now I have to decide if I keep the 16F18877 and poll the IOC flag, or go back to the 16F1937 and poll the Port pin. I'm leaning towards the 16F1937 cause it costs a bit less.